Draft gear



July 29, 1941. H. E. vAN DORN DRAFT GEAR 4 Sheets-Sheet l Filed July 19,1939 July 29, 1941- H. E. VAN DoRN 2,250,920

DRAFT GEAR Filed July 19, 1939 4 Sheets-Sheet 2 1Q umd A S MN Nw N July29, 1941. H. E. VAN Dom 2,259,920

DRAFT GEAR 'Filed July 19, 1939 4 sheets-sheet 3 fir. MMM,

July 29, 1941.

H. E. VAN DoRN DRAFT GEAR Filed July 19, 1939 Y wwf/f Patented July 29,1941 DRAFT GEAR Herbert E. Van Dorn, Chicago, Ill., assigner to 4 TheDornvan Corporatien, a. corporation of Illinois Application July 19,1939, Serial No. 285,257

11 Claims.

In the ordinary draft gear construction for railway cars, the portion inthe region of the spring cushioning means is roughly constructed, in thesense that there is substantially no machining of parts except thedrilling of holes where these are necessary to receive fastenings. As aresult, there is considerable looseness in the draft -gear as a whole,which produces noise and unnecessarily rapid wear, and which preventsaccuracy of adjustment. Although the development of railway equipmenthas been in the direction to provide smooth, noiseless operation, theuseless lost motion in the draft rigging has not heretofore beeneliminated even though the coupler heads are no longer required to movelengthwise more than an inch or so. The reason for this failure toemploy precision work in connection with the construction that providesthe cushioning means, is that the necessary machining to take up allunnecessary slack, in draft gears as heretofore constructed, could onlyhave been done at a prohibitive cost.

The object of the present invention is to provide a draft gear in whichthe coupler shank and the drawbar proper are connected together in sucha manner that there is no unnecessary looseness or lost motion, withoutany considerable increase in the cost over the cost of the old types.

In carrying out my invention, I provide the coupler shank with a housingwhich, when the draft gear is in use, is closed against the entrance ofdirt, which provides machined bearing surfaces for the front end of thedrawbar to permit the necessary relative movements and prevent thosethat are unnecessary or undesirable, and which permits the bearingsurfaces to be adequately lubricated. I'he parts are so constructed thatthe machine work is quite simple and easily done.

The various features of novelty whereby my invention is characterizedwill hereinafter be pointed out with particularity in the claims; but,for a full understanding of my invention and of its objects andadvantages, reference may be had to the following detailed descriptiontaken in connection with the accompanying drawings, wherein:

Figure 1 is a top plan view of a draft gear, including the means foranchoring the same to the car, embodying the present invention, thecoupler head being shown in broken lines and a portion of the couplerbeing omittedFig. 2 is a side view of the assembly shown in Fig. l, aportion of the anchor being broken away to expose the ball and socketjoint; Fig. 3 vis a view partly in top plan and partly in longitudinalsection of the spring housing and the front end of the drawbar; Fig. 4is a central longitudinal section through the parts shown in Fig. 3;Fig. 5 is a section on line 5-5 of Fig. 3; Fig. 6 is a section taken online 6 6 of Fig. 4; andv Fig. 7 is a section taken on line l-l of Fig.4.

Referring to the drawings, I represents the shank of a so-calledtight-lock coupler. This shank is enlarged at its rear end into theformof a housing 2 which is open at its rear end. The coupler shank, as iscustomary, is hollow and, therefore, to close the front end of thehousing, I` form a transverse wall or partition 3 at the point where thehousing merges into the shank. The generalshape of the housingv intransverse section is rectangular. The central longitudinal panels ofthe top and bottom walls are bulged upwardly and downwardly,respectively, as indicated at 4, constituting sections of a cylindricalshell havingrits axis coinciding with the longitudinal axis of theshank; the' diameterfof Vthe cylinder being, of course, less than theWidth of the housing. The at portions of the top and bottom Walls; andthe side walls of the housing are provided with shallow'bosses 5 ofconsiderable diameter distributed along the same. Holes 6, ofsubstantial size, are' drilled through the housing walls at the centersof these bosses; these holes being large enough to permit the insertionof a tool for facing the bosses.

In order to take the wear incident to the move-V ment o f the parts of aspring lcushioning unit, I provide what may be termed the wing sectionsof the housing, namely, the sections provided with the bosses justdescribed, with Wearing plates or linings which are inthe formofchannel-shaped members 'l of hard steel, such as manganese steel; thesewearing plates being of such size and shape that all three walls of eachbear against the bosses in the corresponding section of the housing;"the wearing plates being somewhat shorter than the housing to provideroom for stationary stops beyond .the ends thereof. The anges of eachwearing plate are preferably securely fastened to the upper and lowerwalls vof the hous-Y ing, although they need not bel fastened to theYvertical sidewalls. Since the holes 6 through the Abosses are larger inVdiameterl than necessary to receive suitable bolts, the holesin theupper and lower. bosses are provided with fairly thick bushings 8. Shortbolts extend througlrthe iianges on the Wearing platesand throughthesebushings; the heads of the bolts being on the inside and beingcounter-sunk in the wearing plates, and the nuts I9 being on theexterior of the housing.

The rounded portions of the top and bottom walls of the housing can bequickly and easily machined by means of a suitable boring tool insertedthrough 'the rear end of the housing and moved throughout the lengththereof. In order to insure accuracy in the machining, I prefer toprovide the partition 3 at the front end of the housing with a centralopening 4 of considerable diameter; this opening being reamed so as toform an effective bearing for the front end of a boring tool. After themachining has been completed, this opening may be closed by inserting asuitable plug l2 in the same. The machining of the interior of thehousing extends to the open rear end so that the cylindrical interiorsurface and the edge face at the rear end may be completed in oneoperation. The cylindrical inner surfaceof the housing need not becontinuous from end to end, but itv may be in the formof distributedbands, as shown, one such band being at the open end.

Any suitable type of cushion may be employed, as long as its transverseand Vertical dimensions are such as to permit it to be engaged at itsside marginal portions in the troughs of the wearing plates.` Some meansmust be provided, however, to serve as front and rear stops. In orderaccurately to locate these stops, so that; throughout an indefinitenumber of draft gears the distance of the stopsfrom the coupler faceswill be exactlythe same, I do not cast them integral with the housing,but construct themV separately and secure them in the housing.

Inthe arrangement shown, each of these stops is in the form of a tallsquare block I4 which rests upon 'a boss l5, similar to one of thebosses 5, on the bottom wall of the housing, either just in front of orjust behind one of the wearing plates.Y Heavy pins I6 extend through thehousing from top to bottom, each pin passing through one of the blocksM. It willbe seen that the holes through which the pins extend permitthe insertion of a tool'for facing the bosses l5, so that a true bearingface may be provided on each of these bosses, just as in the case of thebosses 5. Since the two forward blocks need not be removed after oncehaving been placed in posi- Ition, the holding pins therefor may be apressed t in the housing Walls and blocks. However, the two rear pinsmust be removable so as to permit the two rear stop blocks tofbe takenout whenY desired. The forward stops are the onesapt to be subjected tothe severest shocks, since the bufling stresses caused by blows onrthecoupler heads tending to drive them rearwardly, and whichV are moresevere than Vthe pulling stresses, must be' absorbed by these stops. Inorder to shield the forward pins I6 against abnormal shearing stresses,I provide each side Wall of the housing, where it 'slopes inwardlyandforwardly `to 'meet the coupler shank, asl indicated at I1,` withalongitudinal rib I8 lying about halfway between the top and bottom ofthe housing. Each of' these ribs has'a thickened edge portion llvwhichbears against the front'face of theA corresponding blockl M; Therefore,there lis'a` directftli'rustjfrom-the' housing against each of theforward stopswhich' transmits Aa portion of thek shock independentlycfthe'hol'dingpins. y 'i p VIn, `the Larrangem'ent shown, ftheci'ishiorrunit` is aiwellknowfn'type of spring cushion comprising pluralgroups of spring plates 2i! alternating with rigid followers 2| andspacing plates 22 and 24. The elements lconstituting this unit areassembled and held under initial compression in a drawbar yoke 25. Thisdrawbar yoke is preferably formed integral with a hollow cylindricaldrawbar 26; the opening or window in the yoke, while being shorter thanthe spring cushion in its expanded condition, is of greater height thanthe elements of the cushion, so that the longitudinal members of theyoke do not touch the parts of the spring cushion. This yoke is machinedon the exterior so that when it is set on edge, with one of itslongitudinal members on top and one on the bottom, it fits the internalcylindrical faces of the housing. The angular width of the curved facesof the yoke is less than that of the seats therefor in ,the housing, sothat the housing may rock through a small angle about the longitudinalaxis of the assembly. In order to provide a maximum rocking movementwithout having the longitudinalmembers Yofthe yokes spread apart toofar, I prefer to cut away the innerface of each of these members on arising incline from the outer edges toward the center, as indicated at21; or, in other words, the inner face of each of the longitudinalmembers of the yoke is made convex.

The bearing surfaces between the yoke and the Y housing may belubricated in any suitable way.

- and,3 I meeting along a horizontal plane containing the axis of thecoupler. The two-part'head is provided with aninward projection 32 thatfits into theend of the housing, whereby the housing keeps the twosections of the. head from f spreading apart in a direction transverseto the longitudinal axis. The head is fastened to the housing by meansof four machine screws 3d which extend through the head at what may betermed the four corners thereof and into the'external-thickened portionsor bosses 35 which stiffen the top and bottom walls of the housing inthe regionsv where the rear pins |6` extend through thesame. The dividedhead has a central circular opening 3'5 slightly larger in diameter thanthe body of the drawbar`26. In the edge bounding this openingis anannular groove 3l containing a sealing ring 38 of felt or othersuitabi-e packing material which engages with the periphery of thedrawbar when the structure as a whole is assembled, and prevents dirtandother foreign matter from entering the housing through the opening thatreceivesvthe drawbar.

The drawbar terminates. at its rear end in a ball 39 Yof large diameterwhich is seated in a socket in a suitable rigid anchor fixed to theunder side of the car frame.. In the arrangement shown, the anchorcomprises an upper member do which rests against'and is secured to thecar structure, and a lower member'lt; the

1 two m'embers meeting in a*horizontal planeV and being'securedltogether by" a number of sturdy vertical'lbolts2. Furthermoregin oneofthe meetingj'faces between said members'there may beanVannularlgroove,V while the, otherV may lbe provided withl an annular ribthat fits into the groove and thus relieves the'bolts of some of theshearing stresses which would otherwise be imposed upon the same. Theremay be placed a bellows-like flexible shield 43 in position to cover theentrance of the drawbar into the anchor casting. In the arrangementshown, this device surrounds the drawbar and is clamped at its forwardend tightly against the drawbar, while its rear end lies against a flatfront face of the anchor casting and is secured thereto in a manner toproduce a tight joint.

It will thus be seen that I have produced a simple, rugged draft gearwhich permits the coupler to move longitudinally and angularlyrelatively to the drawbar, in a smooth and soundless manner, and inwhich, by reason of the sealed housing and the facilities forlubricating the engaging, relatively movable surfaces, the conditionsinitially established may be indelinitely maintained. Furthermore,because the stops in front of and behind the spring cushion are appliedafter the housing has been cast, they may be accurately located throughmeasurements for the centers of the bolt holes, made from the face ofthe coupler head as a base line. It will also be seen that the machiningof the housing to permit the attaining of the desired results is verysimple and thus does not add greatly to the cost of the apparatus.

While I have illustrated and described with particularity only a singlepreferred form of my f invention, I do not desire to be limited to theexact structural details thus illustrated and dcscribed; but intend tocover all forms and arN rangements which come within the denitions ofVmy invention constituting the appended claims.

unit embraced by the yoke but standing clear from the longitudinalmembers of the latter, stops in the housing at the ends of the springunits, and a closure for the rear end of the housing extending aroundthe drawbar.

2. In combination, a coupler having at the rear f end arearwardly-opening housing, a drawbar having a cylindrical stemextending a short distance into the rear end of the housing and a yokeincluding parallel longitudinal members at the front end of the stem, aclosure for the open end of the housing surrounding the drawbar stem.the housing and said longitudinal members of the yoke havingcomplementary bearing faces to permit relative longitudinal movementsand relan tive rotary movements of limited extent about the longitudinalaxis of the housing While preventing other relative movements, a cushionunit within the housing embraced by said yoke, and stops in the housingat the ends of said cushion unit.

3. In combination, a coupler having at the rear end a rearwardly-openinghousing, a drawbar having a cylindrical stem extending a short distanceinto the rear end of the housing, a yoke at the front end of the stemincluding longitudinal members spaced apart from each other, a closurefor the open end of the housing surrounding the drawbar stem, thelongitudinal members of the housing and the yoke having complementarybearing faces to permit relative longitudinal cushion unit to restrictthe parts thereof toV movements longitudinally of the housing, and thelongitudinal members of the yoke standing clear of the cushion unit.

4. In combination, a coupler having at its rear end a rearwardiy-openinghousing, said housing having at the top and bottom internal facesforming parts of the surface of a cylinder coaxial with the housing, theinterior of the housing being widened at the sides, longitudinal wearingplates U-shaped in cross section xed in opposite sides of the housing inthe widened portion .of the latter, a drawbar extending into the openrear end of the housing and having bearing faces complementary to andengaged with the cylindrical faces in the housing, and a cushion .unitassociated with the drawbar and extending between and engaged with saidwearing plates.

5. In combination, a coupler having at its rear end a rearwardly-openinghousing, said housing having at the top and bottom internal facesforming parts of the surface of a cylinder coaxial with the housing, theinterior of the housing being widened at the sides, longitudinal wearingplates U-shaped in cross section xed in opposite sides of the housing inthe widened portion of the latter, a vertical block positioned withinthe housing in iront of and behind each wearing plate, a sturdy pinextending vertically through each block and through the top and bottomof the housing, a cushion unit supported by said wearing plates andengaged at its ends with said blocks, and a drawbar device extendinginto the housing from the rear and operatively connected to said cushionunit,

6. A car coupler having at its rear end a rearwardly-opening housing,said housing having in cross-section the shape of a rectangle thecentral portions of the top and bottom sides are in the form of arcs ofa circle having its center at the center of the rectangle, the sidewalls and the top and bottom walls of the housing having large shallowbosses projecting inwardly thereupon, and a U-shaped wearing platearranged in each side of the housing and fitting against the bossesabove, below and beside the same.

7. A car coupler having at its rear end a rearwardly opening housing,said housing having in cross-section the shape of a rectangle thecentral portions of the top and bottom sides are in the form of arcs ofa circle having its center at the center ofthe rectangle, the side wallsand the` top and bottom walls of the housing having large shallow bossesprojecting inwardly therefrom, a

U-shaped wearing plate arranged in each side of portions of the top andbottom sides arein the. form of arcs of va circle having its center atthe center of the rectangle, the side walls and the top l and bottomWalls ofthe housing having large shallow bosses'projecting inwardlyVtherefrom, the walls of the housing having large holes extending throughthe same at the bosses, and bushings in the holes in the top and bottomwalls.

9. A car coupler having at its rear end a rearwardly-opening housing,said housing having in cross-section the shape of a rectangle thecentralivportions of the top and bottom sides are in the form of arcs ofa circle having its center at the center of the rectangle, the` sidewalls and the top and bottom walls of the housing having large shallowbosses projecting inwardly therefrom, a U-shaped wearing plate arrangedin each side of the housing and fitting against the bosses above, belowand beside the same, the bosses on the upper and lower walls havingopenings therein large enough to receive a tool to face the bosses,bushings in said holes, and bolts extending through said bushings andthe corresponding flanges of the wearing plate to secure the Wearingplates to the housing.

10. In combination, a car coupler having at the rear end arearwardly-opening housing, a cylindrical drawbar extending into thehousing, a yoke including parallel longitudinal members xed to the frontend of the drawbar, the housing and the longitudinal members of the yokehaving complementary bearing faces in the form of surfaces of revolutionabout the longitudinal axis of the housing, Vmeans to lubrcate saidfaces, a spring cushion unit embraced by the yoke but standing clearfrom the longitudinal members of the latter, stops in the housing at theends of the spring unit, a closure for the rear end of the housingextending around the drawbar, and means to seal the joint between thedrawbar and the closure.

11. In combination, a coupler having at the rear end a closedhousingprovided with an opening in its rear end, a drawbar having acylindrical stem extending through said opening into the housing and ayoke at the front end of the stem, said yoke including parallellongitudinal members, sealing means around the shaft at said opening toprevent the entrance of foreign matter through the latter, the housingand the longitudinal members of the yoke having complementary bearingfaces to permit relative longitudinal movements and relative rotarymovements of limited extent about the longitudinal axis of the housingwhile preventing other relative movements, a cushion unit within thehousing embraced by said yoke, stops in the housing at the ends of saidcushion unit, and-means to introduce a lubricant into the interior ofthe housing.

HERBERT E. VAN DORN.

